/Engine/Source/Runtime/Experimental/Chaos/Public/Chaos/Collision/PBDCollisionContainerSolver.h
Set the maximum number of constraints the solver will have to handle. This will be called only once per tick, so containers resized here will not have to resize again this tick so that pointers to elements in the container will remain valid for the tick (but not beyond).
virtual void Reset ( const int32 MaxConstraints )